Author(s): COCHRANE, D., CINELLI, M., Institution: WILFRID LAURIER UNIVERSITY, Country: CANADA, Abstract-ID: 1784

INTRODUCTION:
Athletes returning to sport from a sports related concussion (SRC) are 1.5-3.4 times more likely to sustain a musculoskeletal injury than their non-concussed teammates[1]. It has been proposed that following an SRC athletes may be experiencing visuomotor integration deficits affecting their perceptual attunement to their action boundaries[2]. The current study aimed to determine whether VMI deficits exist in recently concussed athletes at RTS-6 and 30 days post RTS-6, and whether a dual task is required to detect these potential deficits by testing recently concussed athletes and their non-concussed teammates on an aperture crossing paradigm as a single task (ST) and dual task (DT). We expected recently concussed athletes to demonstrate greater variability and reduced performance under the DT at and 30 days post RTS-6.
METHODS:
5 recently concussed team sport athletes (CONC; male=1; 20.6±2.4yrs) and 5 sex-, sport-, and position-matched controls (ATH; male=1; 19.8 ±1.6yrs) were immersed in a virtual environment using an HTC Vive Pro2 head mounted display (HMD). Participants approached a set of doors from a distance of 7.5m. Initially open, the doors began to close at a rate ranging from 0.9-1.1m/s*participant’s preferred walking speed when the participant was 4m from the doors. In the first block (ST) participants were instructed to pass through the aperture when they width of the doors equaled their shoulder width. A second block (DT) added serial subtraction to the door crossing task to increase the cognitive load. The HMD recorded the participants’ head position in space at 90Hz, the aperture width at time of crossing (ApWTOC) was outputted to determine each participant’s attunement (i.e., ApWToC/shoulder width). Both groups were tested at two time points (TP): 1) at RTS-6 (TP1) and 2) 30 days later (TP2).
RESULTS:
At TP1 both groups performed similarly, with worse attunement scores on the DT [CONC: 1.93±0.33, ATH: 1.85±.40] compared to the ST [CONC: 1.82±1.60, ATH: 1.65±.49]. A large effect of task by group [np2=.190] and timepoint by group [p=.008, np2=.609] was observed, driven by CONC performing worse on the ST [1.99±.09] at TP2 than the DT [1.79±.23]. A significant effect of time point [p=.001, np2=.760] and task [p<.001, np2=.779], and a significant interaction of time point by group [p=.008, np2=.602] was observed for the variability of attunement scores. Both groups consistency was similar at TP1, with better consistency on the ST than DT, while at TP2 CONC consistency stayed the same as at TP1 with ATH consistency improving [ATH ST: d= 1.21, ATH DT: d=1.12].
CONCLUSION:
Findings indicate that non-concussed athletes improve on task performance when presented with a novel task on more than one occasion, while recently concussed athletes may not be adapting to novel tasks despite clearing the RTS protocol.

1. McPherson, A. L. Am J Sports Med 2019
2. Eagle, S. R. Clin J Sport Med 2021